1. A person who is a lightweight to the effects of (thc) the active ingredient in marijuana.
2.(MERRIAM-WEBSTER) A person affected with a mental disability who exhibits exceptional skill or brilliance in some limited field.

"Dude, you've only hit it twice and ur an idoit savant!"

"Okay, you can't tie your shoes but you can draw me a masterpiece?! You Idoit savant!